When making characters for your convention game, then the first things to bear in mind are :
Make them appropriate to the scenario (not just the setting).
Ensure they’re different enough (in feel and statistics) to give a broad flavour and give everyone their moment to shine
So, with that in mind, here are a few pointers:
When someone makes a character and gives themselves a big skill in Climbing, that means they definitely want shizzle to climb. They want to climb the ass off something and lower a rope down for their less able comrades to scramble up in their wake. When it comes to a point in the story to shine, that’s one of their cues. Same goes when you’re handing out your pre-gen characters at a con. If you’ve given someone a character with Ninja 20, and then have a story devoid of the opportunity to ninja stuff, you’re missing a trick and the player will tend to feel cheated. What’s more, he’ll wander off piste looking for opportunities to ninja stuff, because that’s what the numbers are telling him to do.
Conversely, its also fine to have some skills or advantages in terms of flavour. You might not envisage there being many poetry competitions in your samurai game, but if you want a character to be a warrior poet, then giving them some “compose” skill is not necessarily a bad thing. Just be aware that your players may well try to do something they’re good at. Go figure.
This all works for disadvantages and such too. If someone’s got a phobia of dogs, then its good to stick a big-ass slavering Doberman in there somewhere. When a player reads that he’s got an enemy who’s out to kill him and then you never see or hear from this dark nemesis, its largely disappointment rather than relief that people tend to feel.
In terms of having the correct and appropriate skills for the job, its worth building in some multiple redundancy – for example having only one character able to heal wounds is asking for the medic to die in a freak die-rolling accident in the first few minutes. Be careful to “big up” the main player though, in their description, background, rank or whatever else. Players can have a tendency to look for a number on their sheet and if they’ve got something even vaguely worth rolling, the dice will be clattering way before the real expert has the chance to step forward. So in a similar way to not letting bullies mouth off and giving everyone a chance to have their say in a session, make sure everyone gets a fair shake of the dice too. Literally.
Aside from game statistics or rules differences, its well worth making the character’s character suitably different. Giving people a “marker” to work with can really help others latch on to them. An outrageous hat with peacock feather and loud manner versus dark unassuming attire and a croaky voice, however you do it, try to make each character have some visual or other schtick so that other players will remember them and differentiate easily. How many of the Seven Samurai can you remember? The old kindly samurai, his portly old friend, the young, rash idealist, the stoic duellist, comedian, brash farmer’s son. That’s all off the top of my head. Think Magnificent Seven and there’s the guy in black, the kid, the dude with the knives… now I’m struggling. Make your characters clear in focus and give them a stand out Thing so that people will remember them easily.
There’s plenty more where that came from, but that should get you started!